tree 508d7644d2d27fe6c8b747c819f42e36fc89a4c3
parent fe5c421dd0c4ec453aa99fca0e94816396122f68
author Dimitris Papastamos <dimitris.papastamos@arm.com> 1527763113 +0100
committer Dimitris Papastamos <dimitris.papastamos@arm.com> 1528378485 +0100

Fast path SMCCC_ARCH_WORKAROUND_1 calls from AArch32

When SMCCC_ARCH_WORKAROUND_1 is invoked from a lower EL running in
AArch32 state, ensure that the SMC call will take a shortcut in EL3.
This minimizes the time it takes to apply the mitigation in EL3.

When lower ELs run in AArch32, it is preferred that they execute the
`BPIALL` instruction to invalidate the BTB.  However, on some cores
the `BPIALL` instruction may be a no-op and thus would benefit from
making the SMCCC_ARCH_WORKAROUND_1 call go through the fast path.

Change-Id: Ia38abd92efe2c4b4a8efa7b70f260e43c5bda8a5
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>